Messages in this thread | | | Date | Fri, 29 Jun 2012 02:22:56 -0700 | From | Joel Becker <> | Subject | Re: [PATCH v4 1/2] aio: make kiocb->private NUll in init_sync_kiocb() |
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On Thu, Jun 28, 2012 at 03:39:56PM -0700, Andrew Morton wrote: > On Wed, 27 Jun 2012 17:09:54 +0800 > Junxiao Bi <junxiao.bi@oracle.com> wrote: > > > Ocfs2 uses kiocb.*private as a flag of unsigned long size. In > > commit a11f7e6 ocfs2: serialize unaligned aio, the unaligned > > io flag is involved in it to serialize the unaligned aio. As > > *private is not initialized in init_sync_kiocb() of do_sync_write(), > > this unaligned io flag may be unexpectly set in an aligned dio. > > And this will cause OCFS2_I(inode)->ip_unaligned_aio decreased > > to -1 in ocfs2_dio_end_io(), thus the following unaligned dio > > will hang forever at ocfs2_aiodio_wait() in ocfs2_file_aio_write(). > > > > Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> > > Cc: stable@vger.kernel.org > > Acked-by: Jeff Moyer <jmoyer@redhat.com> > > Acked-by: Joel Becker <jlbec@evilplan.org> > > --- > > include/linux/aio.h | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/include/linux/aio.h b/include/linux/aio.h > > index 2314ad8..b1a520e 100644 > > --- a/include/linux/aio.h > > +++ b/include/linux/aio.h > > @@ -140,6 +140,7 @@ struct kiocb { > > (x)->ki_dtor = NULL; \ > > (x)->ki_obj.tsk = tsk; \ > > (x)->ki_user_data = 0; \ > > + (x)->private = NULL; \ > > } while (0) > > > > #define AIO_RING_MAGIC 0xa10a10a1 > > hm, that code is rather cruddy. Pointless macromania.
Agreed.
> If we do this: > > static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) > { > *kiocb = (struct kiocb) { > .ki_users = 1, > .ki_key = KIOCB_SYNC_KEY, > .ki_filp = filp, > .ki_obj.tsk = current, > }; > } > > then fs/read_write.o's .text is shrunk from 9857 bytes to 9714, which > is rather a lot. > > But that's all rather irrelevant to your bugfix.
I like your solution. Junxiao, if you send me that version, I'd be happy to take it.
Joel
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